/**
 * KopsoxFramework
 * Copyright (C) 2010 Free Software Foundation, Inc. <http://fsf.org/>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.kopsox.validation.impl.value;

import java.io.Serializable;

import org.kopsox.comm.message.ValueMessage;
import org.kopsox.comm.message.impl.ErrorMessageImpl;
import org.kopsox.data.Value;
import org.kopsox.general.priority.PriorityEnum;
import org.kopsox.general.type.ErrorTypeEnum;
import org.kopsox.general.type.ValueTypeEnum;
import org.kopsox.validation.Validator;
import org.kopsox.validation.impl.AbstractValidator;

/**
 * Checks if the type of the new value is the same as the type from the old value
 * 
 * @author Konrad Renner - 08.09.2010
 *
 */
public final class TypeValidator extends AbstractValidator {

	private static final long serialVersionUID = 1639404994894335920L;
	private final static String name = "TypeValidator";
	
	public TypeValidator() {
		setPriority(PriorityEnum.HIGHEST.getPriority());
	}
	
	/* (non-Javadoc)
	 * @see org.kopsox.validation.Validator#validateValueMessage(org.kopsox.comm.message.ValueMessage)
	 */
	@Override
	public boolean validateValueMessage(ValueMessage value) {
		super.errorMessages.clear();
		boolean ok = true;
		
		Value<Serializable> v = value.getMessageValue();
		
		if(value.getOldValue() != null && v != null && v.getValue() != null){
			if(!value.getTypeFromOldValue().equals(v.getType())) {
				//If the new value is a String, check if the String can be converted
				if(ValueTypeEnum.STRING.equals(v.getType())) {
					if(value.getTypeFromOldValue()==null || value.getTypeFromOldValue().convert(v.getValue().toString()) == null) {
						ok = false;
						ErrorMessageImpl message = new ErrorMessageImpl(PriorityEnum.HIGHEST.getPriority(), ErrorTypeEnum.FALSETYPE);
						message.setMessageSender(this);
						message.setNameOfErrorSource(v.getValueDescriptor().getName());
						super.errorMessages.add(message);
					}
				}else {
					ok = false;
					ErrorMessageImpl message = new ErrorMessageImpl(PriorityEnum.HIGHEST.getPriority(), ErrorTypeEnum.FALSETYPE);
					message.setMessageSender(this);
					message.setNameOfErrorSource(v.getValueDescriptor().getName());
					super.errorMessages.add(message);
				}
			}
		}
		
		return ok;
	}

	
	public String toString() {
		return name;
	}
	
	/**
	 * Returns true if the Validator is a 'Show-Stopping'-Validator.<br>
	 * A 'Show-Stopping'-Validator is an Validators which stops the validation process, if he fails.<br>
	 * This means, that after this Validator no other Validator is called, if the method 'validateValueMessage' returns false!<br>
	 * <b>NOTE:</b>This Validator is a 'Show-Stopping'-Validator
	 * 
	 * @return boolean
	 */
	@Override
	public boolean isShowStoppingValidator() {
		return true;
	}
	
	/**
	 * The Type-Validator must be called directly after the Readonly and NotNull-Validator.<br>
	 * So this compareTo-Method returns always -1, except the other Validator is also an Typen,NotNull or Readonly-Validator<br>
	 * 
	 * @param o - Validator
	 */
	@Override
	public int compareTo(Validator o) {
		if(o instanceof ReadonlyValidator || o instanceof NotNullValidator) {
			return 1;
		}else if(o instanceof TypeValidator) {
			return 0;
		}
		
		return -1;
	}
}
